With increasing industrial development, digitalized office technologies have experienced great growth and are now rapidly gaining in popularity. For example, a diversity of office machines such as copy machines, printers, fax machines and scanners are utilized to achieve various purposes. The diverse office machines, however, occupy lots of space. Nowadays, a multifunction peripheral having multiple functions in one structural unit, for example the functions of a printer, a scanner, a fax machine and/or a copy machine, is thus developed. As a consequence, the processing capability of the multifunction peripheral is increased and the operative space thereof is reduced.
For enhancing the scanning quality, before the image reading apparatus reads out data, the image reading apparatus should be corrected according to background condition and the light-sensing element. After the correction is implemented, the optical parameters of the light-sensing element will be compensated. Moreover, for increasing the scanning speed, the image reading apparatus has two image sensors to respectively scan the front and back sides of the original document. Since the light beams emitted by these two image sensors have different reflecting effects on the front and back sides of the original document and the sensing efficacy of both image sensors are different, the imaging quality is distinguished. For achieving the similar image quality, it is critical to develop a mechanism for correcting these two image sensors.
The conventional correcting method, however, still has some drawbacks. For example, if the compensated correction position is far from the real scanning position, a distortion correction problem occurs and thus the scanning quality is deteriorated. In addition, if the surface of the correction element is abraded or contaminated by the document that is transported through the transfer path, the distortion correction problem also occurs and thus the scanning quality is deteriorated.
There is a need of providing an image reading apparatus with enhanced correcting efficacy so as to obviate the drawbacks encountered from the prior art.